The cautions that can be given to the friend include the following:
Eating foods from different sources is very advantageous because it ensures that one gets all the necessary food nutrients that are needed for proper growth and development. Getting the necessary food nutrients on the other hand will boost one's immunity and enable one to develop resistance to diseases. Restricting one's food to a limited type of food is very bad and can have fatal consequences.
We "release energy" by doing two things. One is through going to the toilet and not peeing :). When our bodies digest the food we eat, we have to release this leftover energy in the form of fecal matter. Another way how we release energy is when our lives end. When our life ends, our bodies start rotting and releasing energy for other beings.
Answer: D is you answer.
Explanation: Because earth first atmosphere had very little oxygen to support life.
Its is joule because it measures both work and energy